SPR-based assays enable the full functional analysis of bispecific molecules

Area of Science:

• Biochemistry
• Biotechnology
• Immunology

Background:

• Novel biotherapeutics, including bispecific antibodies and fusion proteins, present complex functional characterization challenges.
• Assessing bispecific antibodies requires evaluating two independent binding events and their interdependence, unlike standard antibodies.

Purpose of the Study:

• To develop and validate novel Surface Plasmon Resonance (SPR)-based assay principles for the comprehensive functional characterization of bispecific antibodies.
• To address limitations of existing bridging assays, such as potential changes in antigen activity upon immobilization.

Main Methods:

• Development of two SPR-based assay principles: one for simultaneous binding assessment and another for individual target assessment in solution.
• Comparison of data obtained from both assay principles to evaluate their correlation and reliability.

Main Results:

• Both SPR assay principles enable a "full" functional analysis of bispecific CrossMabs within a single assay setup.
• Simultaneous binding can be accurately calculated from individual target readouts, demonstrating a good correlation between the two methods.

Conclusions:

• The validated SPR assay principles provide efficient and reliable methods for the functional characterization of complex biotherapeutics.
• These assays facilitate efficient drug development by enabling comprehensive analysis of bispecific antibody binding characteristics.